March of electron-emitting 'Triffids' science photo of the year

By Tereza Pultarova

Published Monday, March 16, 2015

An electron microscope photograph capturing a forest of electron-emitting nanotubes, dubbed the ‘March of the Triffids’, has won the science photography competition run by the Engineering and Physical Sciences Research Council (EPSRC).

Taken by Bristol University Professor Paul May, the false-colour electron microscope image was selected from a pool of 150 entries by a panel of judges consisting of photo journalists, academics and industry experts.

The image was taken during Professor May’s research into nanotubes, which could be used to make future more durable screens. Explaining the science behind his victorious shot, he said: “Carbon-nanotubes normally grow vertically upwards, like the bristles on a hairbrush, but in contact with water they clump together like wet hair to form 'tepee-like’ structures with a pointy top”.

“We deposited a very thin layer of diamond onto these to lock them into shape. They now form arrays of points, comprising between 10 and 20 carbon nanotubes.”

When high voltage is applied, electrons travel up the nanotubes to the tip of the tepee and are emitted into a vacuum. In the vacuum, they can be made to strike a phosphor screen to give off light.

Each of the nanotubes is about 50,000 times thinner than a human hair.

Professor May said the green, Triffid-reminding, colour of the picture was a result of Photoshop experiments.

“I tried several different false-colour schemes in Photoshop, and when I tried green the tepee structures immediately reminded me of triffids, and hundreds of them together looked like an army on the march - hence the title,” May said.

The competition sought entries in five categories - Discovery, Weird and Wonderful, Equipment, Innovation, and People.

The EPSRC praised four additional images: an electron microscope image of bamboo cells, a picture of a nanometre-thick vapour cell used in atomic physics experiments that displays the interference patterns known as Newton’s Rings, a ‘brain in jar’ photograph illustrating the effect of horror films on brain waves, a photo of the iCub humanoid robot capable of learning as a child how to move and interact with its surroundings and a picture of 3D-printed versions of mathematical constructs such as the Julia Set.

“The quality of the entries is testament to the talents, both scientific and artistic, of the people EPSRC supports,” said EPSRC’s CEO Professor Philip Nelson.

“This competition and these truly inspirational images are a great way for us to engage with academics, connect the general public with research they fund, and inspire everyone to take an interest in science and engineering."

Only researchers who had their work funded through EPSRC were eligable for the awards.